如果else语句没有按预期工作

Question

我不确定为什么它不起作用。即使条件成立，当我点击提交按钮时，它正在运行else语句并返回0。 请帮忙。

XML代码：

<EditText
    android:id="@+id/dog_textView"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:layout_marginTop="72dp"
    android:layout_marginRight="8dp"/> 
<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Submit"
    android:layout_gravity="center_horizontal"
    android:layout_marginTop="16dp"
    android:onClick="submitOrder"/>

MainActivity.java：

public class MainActivity extends AppCompatActivity {

    int playerScore = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void submitOrder(View v){

        EditText editText = (EditText) findViewById(R.id.dog_textView);
        String answer = editText.getText().toString().toUpperCase();
        if (answer == "DOG"){
            playerScore = playerScore + 2;
            Toast toast = Toast.makeText(MainActivity.this,"Your player score is: "+ playerScore ,Toast.LENGTH_SHORT);
            toast.show();
        } else {
            Toast toast = Toast.makeText(MainActivity.this,"Your player score is: "+ playerScore ,Toast.LENGTH_SHORT);
            toast.show();
        }
    }

}